From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Drawing of a modified high-compression cylinder head.
| Identifier | ExFiles\Box 86\1\ scan0147 | |
| Date | 11th May 1939 | |
| Note. DOWEL HOLES TO BE AS ON EB GIS IE NOT ELONGATED. THIS SECTION INCR. TO .275 EXCEPT FOR LOCAL POCKETS REMAINING .175 ADJACENT TO S. PLUG BOSSES. EXHAUST INLET SPARE PLUG DRILLING IS ALTERED BUT POSN. OF BOSS IN CASTING IS UNALTERED. SECTION ON PLUG HOLE. IN EACH CASE CL OF VALVE GUIDE IS MOVED IN .087 TOWARDS CL OF COMBUSTION CHAMBER CL OF PORT IS NOT ALTERED PATTERN TO BLEND IN THUS MODIFON. TO HIGH-COMP CYL. HEAD EX/15322 FOR ALL OTHER DIMENSIONS ETC SEE EB 1237 VALVE GUIDE BOSSES MOVED IN .087 HOLES DRILL TAP & CBORE AS ON EB 1237 .650 DIA BOSSES JOINED AS SHOWN BY TANGENTIAL LINES DRILL .438 DIA. TAP 14MM x 1.25MM PITCH C BORE .562 DIA CENTRE FACING MODIFIED THUS SEE EB GIS DERBY. 2 SHEETS SHEET 1 Ex 16041 | ||